Panel board switch



April 24, 1934- .1. E. CARLSON- PANEL BOARD SWITCH Filed June 6, 1932 2Sheets-Sheet l April 24, 1934. J. E. CARLSON 1,955,434

PANEL BOARD SWITCH Filed June 6, 1952 2 Sheets-Sheet 2 INVENTOR PatentedApr. 24, 1934 UNITED STATES PANEL BOARD SWITCH John E. Carlson,Forestville, Conn., assignor to The Trumbull Electric ManufacturingCompany, Plainville, Conn., a corporation of Connecticut ApplicationJune 6, 1932, Serial No. 615,492

4 Claims.

I with a hinged cover for the fuse compartment.

Another object of the invention is to provide a switch of the abovecharacter in which all the switch operating mechanism is supported in abox which is closed at the front by means of a detachable face plate andaccess to the fuses is normally prevented except through an openingwhich is locked when the switch is closed.

Another object is to provide means for preventing accidental engagementwith the quick' 0 break mechanism when the face plate is removed.

Another object is to provide a simple form of interlocking mechanismcoacting between the quick break mechanism and the door to the fuse 5compartment.

Another object is to provide a simple and effective support for theoperating handle in direct connection with the switch and independentlyof the face plate.

In the form of the invention as shown in the accompanying drawings thepanel board is provided with openings adapted to receive the switchunits. Each switch unit consists of a box and a detachable face plate.The box is detachably secured to the frameworkof the panel board andcontains any suitable type of switch mechanism,

- preferably of the quick make and break construction.

The operating handle is hinged to a bridge across the upper part of thebox and connected to a switch operating crank at the back withintervening snap action mechanism. A guard is provided topreventaccidental contact with the snap action mechanism. The face plate isdetachably connected to the front of the panel board and provided with apassage for the operating handle and an opening for access to the fuses.This opening is closed by means of a hinged door. An interlocking deviceis provided between the door and the snap action mechanism which,however, does not interfere with the removal of the face plate and thedoor. Fig. 1 is a front view of a panel board showing mechanisminvolving my invention. This shows for convenience in illustration aboard for five switch units and the drawing shows the face plates anddoors for two of these units. Two of the other units are omitted and theface plate of the fifth unit is omitted. I Fig. 2 is a side view and:vertical section of the construction shown in Fig. 1.

Fig. 3 is a plan view and partial section of the construction shown inFig. 1 with a box in. place.

Fig. 4 is a perspective view of the box of one of the switch units butomitting the switch mechanism and the fuses.

Fig. 5 is a perspective view of the face plate for a box such as shownin Fig. 4.

Fig. 6 is a front view on a somewhat larger scale of one of the switchboxes with switch actuating mechanism and the guard for the snap actionmechanism; the switch contacts and fuses, however, being omitted.

Fig. 7 is a vertical section of the construction shown in Fig. 6 withthe face plate and its door in place.

Fig. 8 is a horizontal section taken generally on the planes of the line8-8 of Fig. 6 but also showing the face plate in position.

Fig. 9 is a horizontal section taken generally on the plane of the line9-9 of Fig. 6 and showing the faceplate and its door.

Fig. 10 is a fragmentary detail view showing the latch and interlockingmember for the door.

The general panel board construction is fully shown, described andclaimed in an accompanying application-of Herman J. Hammerly, Serial No.615,488 filed June 6th, 1932 although it is shown generally here for abetter understanding of the invention claimed herein.

The panel board is made up of a main panel 15 with side 16 and crossbars such as 17, 18 and 19 at the rear. The panel is provided withsuitable openings such as 20 and 21 for the detachable safety switchunits.

Each switch unit consists of a box 22 and a face plate 23. The boxisprovided with flanges 24 and 25 at the rear which are adapted to besecured to the edges of the cross bars 1'1 and 18 at the rear of thepanel board in any suitable manner.

The body ofthe box is adapted to be inserted through the openingprovided for it in the panel. The face plate 23 is securednot to thebody of the box but to the main panel 15. For this purpose the loweredge of the face plate 23 is provided with a lip or hook-like flange 26offset inwardly just sufficient to hook over the edge 27 of e theopening in-the main panel. The upper edge of the face plate 23 isprovided with a pivoted arm 28 which is adapted to be drawn up behindthe wall 29 at the upper edge of the opening in the main panel by meansof a screw 30 accessible from the front of the face plate.

The switch mechanism per se may be of any suitable construction and willusually include insulating members such as 32 and 33 for supporting theswitch contacts 34 and the fuses 35. The switch contacts are preferablymounted in the upper part of the box and the fuses in the lower part ofthe box and the face plate 23 is provided with an opening 36 throughwhich access may be had to the fuses for inspection and replacement.This fuse opening 36 is normally closed by a door 37 hinged at 38 andprovided with a spring pressed latch bolt 39 adapted to be retracted bya pivoted fingerpiece 40.

Current is supplied to each switch unit from the main line bus bars 42,branches 43 and 44 to screw bolts 45 which extend through the back ofthe box and are connected to the respective line terminals of theswitch. The load terminals 46 are connected to the screw bolts 47 forthe respective switch units.

Each switch unit has an operating crank 50 suitably pivoted in theopposite sides of the box and suitably connected to the movable switchmembers. Any suitable type of snap action mechanism may be provided toinsure a quick break and also a quick make if desired. Such mechanismmay include a hub 51 supporting one end of the operating crank, anoscillating disc 52 having a lost motion connection with the hub andalso a lost motion connection with the operating crank, a spring 53 onthe guide rod 54 connected to this disc and manually operable means foroscillating the hub.

The operating handle 55 is supported by a bridge 56 which extends acrossthe upper end of the box. This bridge preferably has its ends 57 bentrearwardly and secured to the side of the box by riveting, spot weldingor by screws 58. The central part of the bridge is bent into a U-shapedor channeled form 59 to provide a recess for the inner end of the handle55. A countershaft 60 is supported at the rear of the bridge by straps61 which provide bearings for the shaft. The inner end of the shaft 60is square or other irregular cross section to fit in a correspondinglyshaped opening in the inner end of the operating handle. The outer endof the countershaft is provided with an offset crank pin I 62 which isconnected by a link 63 to an extension 64 on the hub so that when theoperating handle 55 is moved up or down movement is transmitted throughthe countershaft 60, the crank pin 62 and the link 63 to the hub 51. Inthis way the snap action mechanism is actuated by the handle 55. Such aconstruction is broadly covered in Hammerly application 521,709, filedMarch 11, 1931.

The bridge and the attached handle are removable from the boxindependently of the link 63 and the snap action mechanism.

In order to prevent accidental engagement with the snap action mechanismI prefer to provide a guard plate 65 which has flanges 66 at oppositeends which may be secured to the box by riveting, spot welding or byscrews 67. This guard covers the inside of the top of the snap actionmechanism, as shown in Figs. 6, 7 and 8.

The face plate 23 as previously mentioned is provided with an opening 36for access to the fuses, which opening is normally closed by a door37-with a latch 39. It is highly desirable, however, that this door beautomatically locked to prevent access to the fuses when the switch ison. I therefore provide an interlocking mechanism between the door andthe hub 51.

The lever 70 is pivoted at 71 to the inside of the box and has a hook 72on one end adapted to fit into a notch 73 in the hub 51. The spring 74normally presses this hook against the hub.

The door 37 is provided with a pin 75 which is interlocked with a hook76 on one arm of the lever 70 when the switch parts are in the closedcircuit position and the switch actuating mechanism is in the positionshown in Figs. 6 and 7. In this position it is impossible to open thedoor 37 because the pin 75 is held by the hook 76 on the interlockinglever 70 and the lever is' held from tilting counter-clockwise becauseof the engagement of the hook 72 with the hub 51.

When the operating handle 55 is moved to open the switch the recess ornotch 73 is brought into the path of the hook 72, whereupon the spring74 pulls the horizontal arm of the interlocking lever upwardly torelease the pin 75 and permit the door 37 to be opened. This guard clipis suitably secured to the center of the bridge 56.

As the door is closed the pin 75 engages the inclined shoulder 77 anddisengages the hook 72 from the notch 73 in the hub 51, thus permittingthe switch to be closed when necessary.

On account of the fact that the timing of the interlocking parts may beimportant in some cases I have provided means for adjusting the hookedend of the lever 70 with respect to the door. This is effected byforming one arm of the interlocking lever 70 of two parts, 78 and 79,which are connected together by one or more screws such as 80 in a slot81 so that in effect the length of the horizontal arm of the interlocklever may be adjusted to bring the hooked end into its proper positionwith respect to the pin 75 on the door of the fuse compartment.

The front plate 23 of the switch unit is provided with an opening 83 forthe operating handle 55. This opening should be large enough to permitof the convenient application of the face plate to the switch box. Inorder to guard the upper and lower edges of this opening I provide aU-shaped clip 84 which has its upper and lower ends extended to coverthe upper and lower edges of the slot 83 as shown in Fig. 7.

In order to permit the locking of the operating handle in the on and of!positions I provide a plate 85 which is suitably secured to the faceplate around the opening 83. This plate 85 has flanges 86 on oppositesides of the handle and these flanges have holes 87 through whichinterlocking or sealing members such as a padlock may be introduced.

According to my invention it will be seen that a panel board may bebuilt up of a plurality of switch units, each independently secured tothe panel board frame and each unit comprising an independently enclosedswitch of the safety type having a face plate substantially flush withthe face of the panel board and with only a projecting operating handle.These switch units can be made up in any size and various units ofvarious sizes can be assembled in a panel board to take care of anyconditions required. It will be seen that each of the switch units isaccessible for the purpose of inspecting and replacing fuses and thatwhen necessary the entire switch unit can be removed and replaced.

I claim:

1. A switch unit including a sheet metal box,-

abridge secured to said box across the open face of the box and havingan offset portion, a handle pivoted in said offset portion, snap actionswitch mechanism in the box actuated by said handle, a face platedetachably secured to the box independently of the bridge and a movabledoor permitting access to a part of the box through the face plate.

2. A switch unit including a sheet metal box, a switch block mounted inone end of the box and having stationary and movable contacts, anoperating crank shaft for the movable contacts at the rear of the block,snap action mechanism in the box detachably connected to said crankshaft, a bridge secured across the'front of the box over said blocksubstantially flush with the front edge of the box, a counter crankshaft pivotally carried by said bridge and connected to the snap actionmechanism, an actuating handle carried by said counter crank shaft andsaid bridge and a face plate secured in place over the entire boxindependentlyof the handle and movable independently of the bridge.

3. A switch unit including a box, a switch block mounted in the box andhaving stationary and movable contacts, an operating crank shaft for themovable contacts at the rear of the block, snap action mechanism in thebox detachably connected to said crank shaft, abridge secured to the boxand extending across the front of the box over said block back of thefront edge of the box,v a counter crank shaft pivotally carried by saidbridge and connected to the snap action mechanism, an actuating handlecarried by said counter crank shaft and said bridge and a face platesecured to the box and removable independently of the bridge and of thehandle.

4. A switch unit including a box, a switch block mounted in the box,stationary and movable contacts mounted on said block, an operatingcrank shaft for the movable contacts mounted at the rear of the block,switch operating mechanism in the box and connected to said crank shaft,a bridge across the front'of the box and over the front of said block, acounter crank shaft pivotally mounted on said bridge and connected tothe switch mechanism, an actuating handle pivotally mounted on saidbridge and operably connected to said counter crank shaft and a faceplate connected in place over the front of the box and removableindependently of the bridge and handle.

JOHN E. CARLSON.

